Effects on Animals | Boreal At Memorial

Effects of Climate Change on Boreal Animals

Large Mammals

As mentioned before, climate change will lead to an increase in forest fire frequency and severity.

This is bad news for caribou (Rangifer tarandus), which rely heavily on lichens for food in the winter: these lichens may take 50 years to recover after a fire (9), so with more and more lichen being lost to fires as the temperatures increase, caribou are going to get pretty hungry in the winter.
If that weren't bad enough, an increase in rain-on-snow events leaves a hard, crusty layer of ice on top of the snow, which makes it harder for the caribou to dig down through the snow to reach what little lichen remains. (9)

It may not be all bad news for the caribou though, as longer growing seasons will result in more high-quality food in the summers. Even this has its downsides though, as it is predicted that moose (Alces alces) habitat my actually expand due to global warming, which will increase competition between the two (9). Furthermore, both species will face increased harassement by increased numbers of pesky insects that will thrive in the warming climate. (9)

References

A caribou (Rangifer tarandus) at Jasper National Park.

source: http://www.pc.gc.ca/eng/pn-np/ab/jasper/natcul/natcul4.aspx

An alder flycatcher (Empidonax alnorum).

source: http://sdakotabirds.com/species/alder_flycatcher_info.htm

Birds
Climate change will have a huge effect on boreal birds:

Loss of trees to increased fires and insect outbreaks means a loss of habitat for many tree-nesting bird species.
Where climate change leads to an earlier spring, insect emergence often peaks early. If migrating birds do not shift their migration timing accordingly, they may not arrive in time to catch the peak insect population, leading to reduced reproduction. It is estimated that for some species, particular populations may decrease by up to 90%! (10)
The reduction in wetlands due to drought means less habitat for many waterbirds and shore birds. (4)

Projected decrease in Alaskan caribou range: red and green lines show projections from two models, blue line is historic change in caribou range.

modified from Joly et al. 2012

Disease
Climate change is expected to increase the rates of infection by a wide variety of diseases in a large number of hosts: (8)

It is thought that bacteria and parasites will thrive in the changing climate, allowing them to survive, transmit, and reproduce at higher rates (8).
As many insect or other invertebrate vectors (e.g. mosquitos or ticks) are responsible for the spread of certain pathogens, it is likely that many of these insects will also thrive in the changing climate, leading to even higher transmission rates.
Finally, hosts may become more susceptible to infection as their immune systems may be weakened by increased stress.